1. Field of the Invention
The present invention relates to an air flotation bar for use in positioning, drying or curing of a continuous planar flexible material such as a printed web, news print, film material or sheet plastic. The present invention more particularly pertains to an air flotation bar which includes two individual air bars in the upper region of the air flotation bar, each having a Coanda slot about its longitudinal outer edge and a third Coanda slot between the two air bars. The outer Coanda slots provide for web flotation and heat transfer, and the third Coanda slot between the outer air bars provides for additional heat transfer air flow and flotation by air impinging upon the web.
2. Description of the Prior Art
Prior art air flotation bars have been up-scaled in physical size to provide an air bar twice the original size for higher flotation clearance and better web control. The detrimental effect of up-sizing is the degradation of the heat transfer coefficient.
The present invention overcomes the disadvantages of the prior art by providing an air flotation bar where the same flotation capability is maintained, as well as enhanced heat transfer. Three small Coanda air slots instead of two larger Coanda air slots provide for an equal Coanda air flow orifice area in addition to a substantially equal distributed air flow.